It's very difficult to develop a proportinal physique at 6'7". Joshua has done it at 6'6" but at that height to become proportional you have to become so muscle bound that you become stiff, lose punching power and gas out quickly. At Wilder's height it is near impossible to become proportional without roiding and hitting some serious iron. Which may help you "look" proportional, but takes away from your boxing. Conversely guys who are rather short like say 5'4" have a much easier time getting proportional in physique and aesthetics. You don't have ot build much mass to develop a proportional physique as a shorter man. But you run the risk of looking like a tree stump when you bulk up like Qawi did. In aesthetics men who are 5'10" to 6' have the easier time developing a proportional and aesthetic physique. They don't have to worry about looking gangly or odd looking and they don't have to worry about looking like a stump when they bulk up either.